Tuesday, April 27, 2010

GOES-13 is America’s New GOES-EAST Satellite

The Geostationary Operational Environmental Satellite known as GOES-13 became the official GOES-EAST satellite on April 14, 2010. GOES-13 was moved from on-orbit storage and into active duty. It is perched 22,300 miles above the equator to spot potentially life-threatening weather, including tropical storm activity in the Atlantic Ocean and Gulf of Mexico.

"Just in time for the 2010 hurricane season, NOAA will have one of its newest, technologically advanced satellites closely tracking these storms – from when they develop to when they dissipate," said Mary Kicza, assistant administrator of the National Oceanic and Atmospheric Administration's (NOAA) Satellite and Information Service in Silver Spring, Md.

NASA's GOES Project, located at NASA's Goddard Space Flight Center in Greenbelt, Md., procures and manages the development and launch of the GOES series of satellites for NOAA on a cost-reimbursable basis. NASA's GOES Project also creates some of the GOES satellite images and GOES satellite imagery animations. NOAA manages the operational environmental satellite program and establishes requirements, provides all funding and distributes environmental satellite data for the United States.

"It is exciting to think that we are now putting into service the best satellites this country has to offer," said Andre' Dress, GOES N-P NASA Deputy Project Manager, at Goddard. "We are really looking forward to see the increase in performance over the older satellites and the improvements in weather prediction."

There are two GOES satellites that cover weather conditions in the U.S. and they are positioned over the eastern and western U.S. The satellite in the GOES EAST position covers weather on the eastern side of the continental U.S., including the Atlantic Ocean and Gulf of Mexico. The GOES WEST position covers the western half of the U.S. and the Eastern Pacific Ocean.

GOES-13 has now replaced GOES-12, which NOAA is shifting in orbit to provide coverage for South America, as part of the Global Earth Observing System of Systems, or GEOSS. GOES-11 continues to occupy the GOES-WEST position.

Initially known as the GOES-N satellite, it was renamed GOES-13 when it achieved geosynchronous orbit. It was launched from Cape Canaveral Air Force Station, Fla. at 6:11 p.m. EDT on May 24, 2006 aboard a Boeing Delta IV rocket.

GOES-13 is the first of three new NOAA geostationary environmental satellites. The other two in the new series are GOES-14, launched in June 2009 and now in orbital storage, and GOES-15, launched on March 4, 2010, and undergoing tests before completing its "check-out" phase, scheduled to be complete in August 2010.

Since the first GOES launch in 1974, these satellites have supplied the data critical for fast, accurate weather forecasts and warnings. The newer GOES series of satellites help relay distress signals from emergency beacons, and are equipped to monitor solar activity, which can impact billions of dollars worth of government and commercial assets in space and on the ground.

NOAA understands and predicts changes in the Earth’s environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.

For more information about NASA's GOES Program visit:
› goespoes.gsfc.nasa.gov

For more information about NOAA, visit:
› www.noaa.gov

Monday, April 26, 2010

NASA Satellite Images Dissect Iceland Volcanic Plume

Iceland's Eyjafjallajökull Volcano
The ongoing eruption of Iceland’s Eyjafjallajokull volcano is seen in this pair of images acquired April 15, 2010, from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA’s Terra spacecraft. At left is a natural-color visible image, while the right image is a composite of MODIS thermal infrared channels. › Full image and caption
On April 15, 2010, the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA’s Terra spacecraft captured these images of the ongoing eruption of Iceland’s Eyjafjallajökull Volcano, which continues to spew ash into the atmosphere and impact air travel worldwide. The left-hand, natural-color visible image shows a brownish, ash-laden plume streaming across the North Atlantic toward the United Kingdom. The right-hand image is a composite of thermal infrared channels. In this rendition, the ash plume appears red, due to the presence of silica-rich material, and the ice-rich clouds appear blue. These MODIS images do not show any evidence of sulfur dioxide clouds, which would appear yellow in the right image. It is likely that any sulfur dioxide signals were obscured by the large amounts of ash. Scientists expect to see a better expression of sulfur dioxide in later images of the plume as the ash settles over time.

Friday, April 23, 2010

NASA Ames Supports Unmanned Aircraft Mission Across the Pacific

Some of NASA's best talent is hidden behind the scenes when Earth science airborne campaigns are being planned and executed around the world. As part of NASA’s Airborne Science Program, several groups from NASA’s Ames Research Center, Moffett Field, Calif., provide key support to ensure the success of these missions.

Today, their legacy continues as they develop the science infrastructure using NASA’s newest tool in its airborne research fleet, the Global Hawk Unmanned Aircraft System (UAS). "It is NASA's first fully autonomous, high altitude, long endurance UAS. It will give scientists the ability to carry payloads to remote regions of the atmosphere and remain there for long durations collecting key measurements," said Michael Craig, research manager at NASA's Ames and project manager for the first Earth science Global Hawk experiment, known as the Global Hawk Pacific (GloPac) mission.

The Global Hawk has a flight duration of more than 30 hours, a maximum altitude of 65,000 feet, a range of 11,000 nautical miles, and a payload capability of more than 1,500 lbs. of scientific instruments. No other manned or unmanned aircraft can meet these performance capabilities. NASA Dryden Flight Research Center, Edwards, Calif., has acquired three of the first seven Global Hawk aircraft produced for the U.S. Air Force and, through an agreement with the manufacturer, Northrop Grumman Corp., Los Angeles, is modifying them for Earth science operations.

The GloPac mission, now underway at Dryden, has completed its first flights with tremendous success and NASA Ames has played a vital role in providing the management, flight planning, meteorological constraints and science instrument infrastructure and communications required with this new platform. GloPac and the Airborne Science Program are funded by the Earth Science Division of NASA's Science Mission Directorate in Washington.

"It's really amazing to see all these state-of-the-art technologies and hard work come together to create such an outstanding capability," said Craig.

GloPac is being conducted in support of NASA’s Aura and A-Train satellite Earth Observation System constellation. The mission will consist of four to five science flights that will take the aircraft over the Pacific south to the equator, north to the Arctic and to the west past Hawaii. The payload includes 11 science instruments that will collect a wide range of atmospheric data, including trace gases and aerosol composition, as well as meteorological parameters.

"These observations are important for understanding processes that control ozone-depleting substances, greenhouse gases that contribute to climate change and pollution that impacts air quality," explained Craig.

There are over 100 people working on the GloPac mission. This includes managers, pilots, scientists, engineers, aircraft ground crew, and other support staff from NASA, the National Oceanic and Atmospheric Administration (NOAA), several universities and others. The NASA team includes members from Ames Research Center, Dryden Flight Research Center, Goddard Space Flight Center, Greenbelt, Md., Jet Propulsion Laboratory, Pasadena, Calif., and NASA Headquarters, Washington.

"This team is transforming the way Earth Science airborne missions will be performed in the future," said Craig.

Several other teams are developing new research missions and applications for the Global Hawk, and NASA is now working on a mobile control center that will give the aircraft truly global coverage. Later this summer, NASA will use the Global Hawk to monitor hurricane development and intensification. Scientists predict that in future years, the aircraft could be used to monitor a number of natural and human-made changes to our planet, including climate change, ice thicknesses, and ecosystems.

Global Hawk program is a collaborative effort between NASA’s Earth Science, the Northrop Grumman Corp., and NOAA.

Thursday, April 22, 2010

Einstein's Theory Fights Off Challengers

Composite image of the galaxy cluster Abell 3376Two new and independent studies have put Einstein's General Theory of Relativity to the test like never before. These results, made using NASA's Chandra X-ray Observatory, show Einstein's theory is still the best game in town.

Each team of scientists took advantage of extensive Chandra observations of galaxy clusters, the largest objects in the Universe bound together by gravity. One result undercuts a rival gravity model to General Relativity, while the other shows that Einstein's theory works over a vast range of times and distances across the cosmos.

The first finding significantly weakens a competitor to General Relativity known as "f(R) gravity".

"If General Relativity were the heavyweight boxing champion, this other theory was hoping to be the upstart contender," said Fabian Schmidt of the California Institute of Technology in Pasadena, who led the study. "Our work shows that the chances of its upsetting the champ are very slim."

In recent years, physicists have turned their attention to competing theories to General Relativity as a possible explanation for the accelerated expansion of the universe. Currently, the most popular explanation for the acceleration is the so-called cosmological constant, which can be understood as energy that exists in empty space. This energy is referred to as dark energy to emphasize that it cannot be directly detected.

In the f(R) theory, the cosmic acceleration comes not from an exotic form of energy but from a modification of the gravitational force. The modified force also affects the rate at which small enhancements of matter can grow over the eons to become massive clusters of galaxies, opening up the possibility of a sensitive test of the theory.

Schmidt and colleagues used mass estimates of 49 galaxy clusters in the local universe from Chandra observations, compared them with theoretical model predictions and studies of supernovas, the cosmic microwave background, and the large-scale distribution of galaxies.

They found no evidence that gravity is different from General Relativity on scales larger than 130 million light years. This limit corresponds to a hundred-fold improvement on the bounds of the modified gravitational force's range that can be set without using the cluster data.

"This is the strongest ever constraint set on an alternative to General Relativity on such large distance scales," said Schmidt. "Our results show that we can probe gravity stringently on cosmological scales by using observations of galaxy clusters."

The reason for this dramatic improvement in constraints can be traced to the greatly enhanced gravitational forces acting in clusters as opposed to the universal background expansion of the universe. The cluster-growth technique also promises to be a good probe of other modified gravity scenarios, such as models motivated by higher- dimensional theories and string theory.

A second, independent study also bolsters General Relativity by directly testing it across cosmological distances and times. Up until now, General Relativity had been verified only using experiments from laboratory to Solar System scales, leaving the door open to the possibility that General Relativity breaks down on much larger scales.

To probe this question, a group at Stanford University compared Chandra observations of how rapidly galaxy clusters have grown over time to the predictions of General Relativity. The result is nearly complete agreement between observation and theory.

“Einstein's theory succeeds again, this time in calculating how many massive clusters have formed under gravity's pull over the last five billion years,” said David Rapetti of the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) at Stanford University and SLAC National Accelerator Laboratory, who led the new study. “Excitingly and reassuringly, our results are the most robust consistency test of General Relativity yet carried out on cosmological scales."

Rapetti and his colleagues based their results on a sample of 238 clusters detected across the whole sky by the now-defunct ROSAT X-ray telescope. These data were enhanced by detailed mass measurements for 71 distant clusters using Chandra, and 23 relatively nearby clusters using ROSAT, and combined with studies of supernovas, the cosmic microwave background, the distribution of galaxies and distance estimates to galaxy clusters.

Galaxy clusters are important objects in the quest to understand the Universe as a whole. Because the observations of the masses of galaxy clusters are directly sensitive to the properties of gravity, they provide crucial information. Other techniques such as observations of supernovas or the distribution of galaxies measure cosmic distances, which depend only on the expansion rate of the universe. In contrast, the cluster technique used by Rapetti and his colleagues measure in addition the growth rate of the cosmic structure, as driven by gravity.

"Cosmic acceleration represents a great challenge to our modern understanding of physics," said Rapetti's co-author Adam Mantz of NASA's Goddard Space Flight Center in Maryland. "Measurements of acceleration have highlighted how little we know about gravity at cosmic scales, but we're now starting to push back our ignorance."

The paper by Fabian Schmidt was published in Physics Review D, Volume 80 in October 2009 and is co-authored by Alexey Vikhlinin of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, and Wayne Hu of the University of Chicago, Illinois. The paper by David Rapetti was recently accepted for publication in the Monthly Notices of the Royal Astronomical Society and is co- authored by Mantz, Steve Allen of KIPAC at Stanford and Harald Ebeling of the Institute for Astronomy in Hawaii.

NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass.

More information, including images and other multimedia, can be found at:


Tuesday, April 20, 2010

Herschel Reveals Ripening Stars Near Rosette Nebula

Big Babies in the Rosette Nebula
This image from the Herschel Space Observatory shows of a portion of the Rosette nebula, a stellar nursery about 5,000 light-years from Earth in the Monoceros, or Unicorn, constellation. › Full image and caption
The Herschel Space Observatory has uncovered a cosmic garden of budding stars, each expected to grow to 10 times the mass of our sun.
The new image can be seen online at http://www.nasa.gov/mission_pages/herschel/hersch20100412a.html. It was taken using infrared light by Herschel, a European Space Agency mission with important NASA participation.
"Herschel can see through cold thickets of dust to where big, baby stars are forming," said Paul Goldsmith, the NASA project scientist for the mission at NASA's Jet Propulsion Laboratory, Pasadena, Calif.
The image shows most of the cloud associated with the Rosette nebula, located about 5,000 light-years from Earth in the constellation Monoceros, the Unicorn. The region contains a family of growing stars, with the oldest and most massive members in the center of the nebula, and younger and less massive generations located farther out in the associated cloud. The nebula's cluster of the most massive stars, located beyond the right edge of the picture, is responsible for hollowing out the cavity. There's enough dust and gas in the entire Rosette cloud to make about 10,000 suns.
The large, embryonic stars uncovered by Herschel are thought to be a younger generation. They are located inside the tips of pillars that appear to branch out from thicker cloud material. The pillars were, in fact, excavated by the nebula's massive star cluster. Winds and radiation from those stars pushed less dense material away from the pillars, and probably triggered the birth of the big stars inside the finger-like structures. In fact, the pillars point to the location of the massive nebula stars.
The intermediate-mass stellar embryos, each a couple of times as massive as the sun, are located in the redder regions of the image. The small spots near the center of the image are lower-mass embryonic stars, similar in mass to the sun.
Astronomers study regions like the Rosette not only to learn how stars form in our Milky Way, but also to get a better idea of what's going on in distant galaxies. When astronomers look at faraway galaxies, they are seeing light from regions that are bursting with massive stars. In order to compare our galaxy to distant ones, it is therefore important to understand high-mass star formation.
Herschel collects the infrared light from dust. The infrared light is color-coded as follows: light with a wavelength of 70 microns is blue; 160-micron light is green; and 250-micron light is red. The observations were made with Herschel's Photoconductor Array Camera and Spectrometer and the Spectral and Photometric Imaging Receiver instruments.
The principal investigator of this research is Frédérique Motte of the French National Center of Scientific Research and Atomic and Alternative Energies Center, Paris-Saclay, France (see http://hobys-herschel.cea.fr). Motte was a postdoctoral fellow at the California Institute of Technology in Pasadena.
Herschel is a European Space Agency cornerstone mission, with science instruments provided by a consortia of European institutes and with important participation by NASA. NASA's Herschel Project Office is based at JPL. JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at Caltech in Pasadena, supports the U.S. astronomical community. Caltech manages JPL for NASA.
More information is online at http://www.herschel.caltech.edu , http://www.nasa.gov/herschelhttp://www.esa.int/SPECIALS/Herschel/index.html

Monday, April 19, 2010

Navigator Technology Takes GPS to a New High

GPS navigational devices are as ubiquitous as cell phones, freely used by commercial and government users alike to determine location, time, and velocity. These tools, however, are only as good as the signals they receive. Now, NASA engineers have found a way to improve the reception of those signals.

GPS, which stands for the Global Positioning System, is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense. GPS originally was intended for military uses, but in the 1980s, the government made the system available for civilian use. GPS systems now are available to users worldwide who need accurate positioning, navigation, and timing services.

Thanks to a team of engineers from the NASA Goddard Space Flight Center in Greenbelt, Md., spacecraft operating in weak-signal areas — such as geosynchronous orbits where communications and weather satellites typically operate — will be able to acquire and track the weak GPS signals to determine their locations, much like motorists who use GPS to determine where they are. For their work developing the Navigator GPS receiver, the Goddard team was nominated for the coveted NASA "Invention of the Year" award, a prize reserved for NASA employees who have secured patents for their inventions. An announcement is expected shortly.

Although millions of people rely on GPS receivers today for terrestrial applications, onboard GPS navigation for spaceflight operations has been much more challenging — particularly for spacecraft operating above the GPS constellation, which is about 20,200 kilometers (12,727 miles) above Earth in an area normally referred to as high-Earth orbit. That is because existing GPS receivers could not adequately pick up the GPS signal, which is transmitted toward Earth, not away from it. As a result, spacecraft above the constellation could not reliably use GPS for tracking and navigational purposes, forcing them to use more expensive ground-tracking assets.

Seeing an opportunity to help lower mission costs, the Navigator team, led by Goddard engineer Luke Winternitz, used Research and Development (R&D) funding to develop algorithms and hardware for a prototype spacecraft GPS receiver that would allow spacecraft to acquire and track weak GPS signals at an altitude of 100,000 km (62,137 miles) — well above the GPS constellation, roughly one quarter of the distance to the moon.

"The R&D investment allowed us to develop the weak-signal Navigator GPS receiver and bring it to fruition," Winternitz says. "Proof of the value of this investment lies in the explosion of flight opportunities and commercialization ventures that have followed."

Since its development, the technology has secured flight opportunities on several new missions. Navigator will serve as the primary navigation sensor on NASA’s Global Precipitation Measurement Mission (GPM), which will study global rain and snowfall when it launches in 2013.

It is considered the enabling navigation technology for another Goddard-managed project, the Magnetospheric MultiScale (MMS) mission. The mission is made up of four identically instrumented spacecraft that will fly in formation in a very high-altitude Earth orbit, while measuring the 3-D structure and dynamics of Earth’s protective magnetosphere. The mission will rely on the Navigator GPS receiver’s improved sensitivity to help the satellites maintain their precise orbital position.

The Air Force Research Laboratory (AFRL) at Kirtland Air Force Base, N.M. is planning to use a Navigator engineering test unit in its "Plug-and-Play" spacecraft, an experimental satellite that can be developed and launched within days because it uses components that hook together in a manner similar to how a computer adds drives or printers via a Universal Serial Bus interface.

The Navigator team also has delivered an engineering test unit to the next-generation weather satellite called GOES-R, which the National Oceanic and Atmospheric Administration plans to launch in 2015. The contractor developing the spacecraft may use Navigator's signal-processing design in the spacecraft’s GPS receiver.

Broad Reach Engineering, an aerospace engineering firm that operates offices in Colorado and Arizona, meanwhile, is pursuing a commercial license for the Navigator signal-processing technology. It plans to use the technology to build a GPS unit for a U.S. government program currently under development. The company also plans to use Navigator to develop other products that could be used in potential commercial satellite programs or scientific missions, says Dan Smith, a Broad Reach project manager.

And if those successes weren't enough, Navigator proved its mettle during a first-of-its-kind experiment carried out during STS-125, the Hubble Space Telescope Servicing Mission last year. While astronauts rendezvoused with and grappled the telescope, the experiment used radar measurements of GPS signals that were reflected off the Hubble to provide range estimates during docking and undocking, proving a key relative navigation sensing technology that could potentially be used in a robotic rendezvous with the Hubble in the future.

"No question. The Navigator team has experienced an incredible level of success," says John Carl Adams, an assistant chief of technology for Goddard’s Applied Engineering and Technology Directorate’s mission engineering and systems analysis division. "I attribute their accomplishment to technical know-how, but also to a healthy entrepreneurial spirit. These guys saw a need and developed a solution, which is now driving down mission costs for civilian and military space programs and extending the range of spacecraft GPS sensing to geosynchronous orbits and beyond."

More Advances Planned

The team is now looking to further improve the technology.

Winternitz and his team are developing the next-generation Navigator receiver — one that can acquire the GPS signal even if the spacecraft carrying the receiver is located at lunar distances. Such a capability would reduce mission operational costs because ground controllers could track spacecraft via GPS rather than with expensive ground stations.

"We expect that the evolution of Navigator’s capabilities will open up a host of new applications and funding sources, including exploration and high-altitude science missions," Winternitz says. "Navigator’s selling points will continue to be that it can offer better navigation performance in weak-signal and highly dynamic environments."

Saturday, April 17, 2010

NASAs Global Hawk Completes First Science Flight

The Global Hawk can fly autonomously to altitudes above 60,000 feet   -- roughly twice as high as a commercial airliner -- and as far as   11,000 nautical miles.
The Global Hawk can fly autonomously to altitudes above 60,000 feet -- roughly twice as high as a commercial airliner -- and as far as 11,000 nautical miles. Operators pre-program a flight path, and then the plane flies itself for as long as 30 hours. › Larger image
NASA has successfully completed the first science flight of the Global Hawk unpiloted aircraft system over the Pacific Ocean. The flight was the first of five scheduled for this month's Global Hawk Pacific, or GloPac, mission to study atmospheric science over the Pacific and Arctic oceans.
The Global Hawk is a robotic plane that can fly autonomously to altitudes above 18,288 meters (60,000 feet) -- roughly twice as high as a commercial airliner -- and as far as 20,372 kilometers (11,000 nautical miles), which is half the circumference of Earth. Operators pre-program a flight path, then the plane flies itself for as long as 30 hours, staying in contact through satellite and line-of-site communications links to a ground control station at NASA's Dryden Flight Research Center in California's Mojave Desert.
"The Global Hawk is a revolutionary aircraft for science because of its enormous range and endurance," said Paul Newman, co-mission scientist for GloPac and an atmospheric scientist from NASA's Goddard Space Flight Center in Greenbelt, Md. "No other science platform provides the range and time to sample rapidly evolving atmospheric phenomena. This mission is our first opportunity to demonstrate the unique capabilities of this plane, while gathering atmospheric data in a region that is poorly sampled."
GloPac researchers plan to directly measure and sample greenhouse gases, ozone-depleting substances, aerosols and constituents of air quality in the upper troposphere and lower stratosphere. GloPac's measurements will cover longer time periods and greater geographic distances than any other science aircraft.
During Wednesday's flight, the plane flew approximately 8,334 kilometers (4,500 nautical miles) along a flight path that took it to 150.3 degrees West longitude, and 54.6 degrees North latitude, just south of Alaska's Kodiak Island. The flight lasted just over 14 hours and flew up to 18,562 meters (60,900 feet). The mission is a joint project with the National Oceanic and Atmospheric Administration, or NOAA.
The plane carries 11 instruments to sample the chemical composition of the troposphere and stratosphere, including two from NASA's Jet Propulsion Laboratory, Pasadena, Calif.. The instruments profile the dynamics and meteorology of both layers and observe the distribution of clouds and aerosol particles. Project scientists expect to take observations from the equator north to the Arctic Circle and west of Hawaii.
Although the plane is designed to fly on its own, pilots can change its course or altitude based on interesting atmospheric phenomena ahead. Researchers have the ability via communications links to control their instruments from the ground.
"The Global Hawk is a fantastic platform because it gives us expanded access to the atmosphere beyond what we have with piloted aircraft," said David Fahey, co-mission scientist and a research physicist at NOAA's Earth System Research Laboratory in Boulder, Colo. "We can go to regions we couldn't reach or go to previously explored regions and study them for extended periods that are impossible with conventional planes."
The timing of GloPac flights should allow scientists to observe the breakup of the polar vortex. The vortex is a large-scale cyclone in the upper troposphere and lower stratosphere that dominates winter weather patterns around the Arctic and is particularly important for understanding ozone depletion in the Northern Hemisphere.
Scientists also expect to gather high-altitude data between 13,716 and 19,812 meters (45,000 and 65,000 feet), where many greenhouse gases and ozone-depleting substances are destroyed. They will measure dust, smoke and pollution that cross the Pacific from Asia and Siberia and affect U.S. air quality.
Global Hawk will make several flights under NASA's Aura satellite and other "A-train" Earth-observing satellites, "allowing us to calibrate and confirm what we see from space," Newman added. GloPac is specifically being conducted in conjunction with NASA's Aura Validation Experiment.
GloPac includes more than 130 researchers and technicians from Goddard, Dryden Flight Research Center, JPL, and Ames Research Center in Moffett Field, Calif. Also involved are NOAA's Earth System Research Laboratory; the University of California, Santa Cruz; Droplet Measurement Technologies of Boulder, Colo.; and the University of Denver.
NASA Dryden and the Northrop Grumman Corp. of Rancho Bernardo, Calif., signed a Space Act Agreement to re-fit and maintain three Global Hawks transferred from the U.S. Air Force for use in high-altitude, long-duration Earth science missions.
For more on GloPac, visit: http://www.nasa.gov/topics/earth/features/global-hawk.html . JPL is managed for NASA by the California Institute of Technology in Pasadena.
For more information on the GloPac instruments, see: http://www.nasa.gov/centers/dryden/research/GloPac/glopac_instruments.html

Friday, April 16, 2010

Small Companion to Brown Dwarf

As our telescopes grow more powerful, astronomers are uncovering objects that defy conventional wisdom. The latest example is the discovery of a planet-like object circling a brown dwarf. It's the right size for a planet, estimated to be 5-10 times the mass of Jupiter. But the object formed in less than 1 million years -- the approximate age of the brown dwarf -- and much faster than the predicted time it takes to build planets according to some theories.

Kamen Todorov of Penn State University and co-investigators used the keen eyesight of the Hubble Space Telescope and the Gemini Observatory to directly image the companion of the brown dwarf, which was uncovered in a survey of 32 young brown dwarfs in the Taurus star-forming region. Brown dwarfs are objects that typically are tens of times the mass of Jupiter and are too small to sustain nuclear fusion to shine as stars do.

The mystery object orbits the nearby brown dwarf at a separation of approximately 2.25 billion miles (3.6 billion kilometers -- which is between the distances of Saturn and Uranus from the Sun). The team's research is being published in an upcoming issue of The Astrophysical Journal.

There has been a lot of discussion in the context of the Pluto debate over how small an object can be and still be called a planet. This new observation addresses the question at the other end of the size spectrum: How small can an object be and still be a brown dwarf rather than a planet? This new companion is within the range of masses observed for planets around stars -- less than 15 Jupiter masses. But should it be called a planet? The answer is strongly connected to the mechanism by which the companion most likely formed.

There are three possible formation scenarios: Dust in a circumstellar disk slowly agglomerates to form a rocky planet 10 times larger than Earth, which then accumulates a large gaseous envelope; a lump of gas in the disk quickly collapses to form an object the size of a gas giant planet; or, rather than forming in a disk, a companion forms directly from the collapse of the vast cloud of gas and dust in the same manner as a star (or brown dwarf).

If the last scenario is correct, then this discovery demonstrates that planetary-mass bodies can be made through the same mechanism that builds stars. This is the likely solution because the companion is too young to have formed by the first scenario, which is very slow. The second mechanism occurs rapidly, but the disk around the central brown dwarf probably did not contain enough material to make an object with a mass of 5-10 Jupiter masses.

"The most interesting implication of this result is that it shows that the process that makes binary stars extends all the way down to planetary masses. So it appears that nature is able to make planetary-mass companions through two very different mechanisms," says team member Kevin Luhman of the Center for Exoplanets and Habitable Worlds at Penn State University. If the mystery companion formed through cloud collapse and fragmentation, as stellar binary systems do, then it is not a planet by definition because planets build up inside disks.

The mass of the companion is estimated by comparing its brightness to the luminosities predicted by theoretical evolutionary models for objects at various masses for an age of 1 millon years.

Further supporting evidence comes from the presence of a very nearby binary system that contains a small red star and a brown dwarf. Luhman thinks that all four objects may have formed in the same cloud collapse, making this in actuality a quadruple system. "The configuration closely resembles quadruple star systems, suggesting that all of its components formed like stars," says Luhman.

Thursday, April 15, 2010

The Setting Sun

The sun sets on the space shuttle Discovery’s almost empty cargo bay at the successful conclusion of the mission, as the seven astronauts inside the crew cabin approach one of the final mission chores--that of closing the cargo bay doors.

Tuesday, April 13, 2010

Cassini Doubleheader: Flying By Titan and Dione

Composite of Saturn's moons Titan and Dione Composite of two images from NASA's Cassini spacecraft of Saturn's moons Titan (left) and Dione (right). › Full image and caption (Titan) | › Full image and caption (Dione)
In a special double flyby early next week, NASA's Cassini spacecraft will visit Saturn's moons Titan and Dione within a period of about a day and a half, with no maneuvers in between. A fortuitous cosmic alignment allows Cassini to attempt this doubleheader, and the interest in swinging by Dione influenced the design of its extended mission.

The Titan flyby, planned for Monday, April 5, will take Cassini to within about 7,500 kilometers (4,700 miles) of the moon's surface. The distance is relatively long as far as encounters go, but it works to the advantage of Cassini's imaging science subsystem. Cassini's cameras will be able to stare at Titan's haze-shrouded surface for a longer time and capture high-resolution pictures of the Belet and Senkyo areas, dark regions around the equator that ripple with sand dunes.

In the early morning of Wednesday, April 7 in UTC time zones, which is around 9 p.m. on Tuesday, April 6 in California, Cassini will make its closest approach to the medium-sized icy moon Dione. Cassini will plunge to within about 500 kilometers (300 miles) of Dione's surface.

This is only Cassini's second close encounter with Dione. The first flyby in October 2005, and findings from the Voyager spacecraft in the 1990s, hinted that the moon could be sending out a wisp of charged particles into the magnetic field around Saturn and potentially exhaling a diffuse plume that contributes material to one of the planet's rings. Like Enceladus, Saturn's more famous moon with a plume, Dione features bright, fresh fractures. But if there were a plume on Dione, it would certainly be subtler and produce less material.

Cassini plans to use its magnetometer and fields and particles instruments to see if it can find evidence of activity at Dione. Thermal mapping by the composite infrared spectrometer will also help in that search. In addition, the visual and infrared mapping spectrometer will examine dark material found on Dione. Scientists would like to understand the source of this dark material.

Cassini has made three previous double flybys and another two are planned in the years ahead. The mission is nearing the end of its first extension, known as the Equinox mission. It will begin its second mission extension, known as the Solstice Mission, in October 2010.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter was designed, developed and assembled at JPL.

More information about the Titan flyby, dubbed "T67," is available at:
http://saturn.jpl.nasa.gov/mission/flybys/titan20100405/ .

More information about the Dione flyby, dubbed "D2," is available at:

Monday, April 12, 2010

Stofan's Management Skills Raise Glenn's Profile

Andrew Stofan, Center Director for NASA's Lewis Research Center (now NASA Glenn) from 1982-1986, helped the center gain greater visibility and respect within NASA. An internationally recognized researcher and manager, Stofan transitioned Lewis into mainstream NASA and brought in many new projects for the center.

Former Center Director Andrew Stofan in 1998Throughout his 30 years at NASA, Stofan held numerous managerial and administrative positions. His technical expertise was bolstered by a healthy dose of "charisma and confidence" that gained him the admiration of the rank and file within the agency and contracting organizations.

Stofan began his career as a research engineer at Lewis Research Center in 1958 and later joined the Propellant Systems Section of the original Centaur Project Office, where he began a steady climb through the tiers of management to become Director of Launch Vehicles in 1974. Much of the Titan-Centaur vehicle's success can be attributed to Stofan's leadership of NASA, the Air Force and aerospace industry teams. By 1978, Stofan was called to Headquarters to serve first as the Deputy Associate Administrator for the Office of Space Science, and then as Associate Administrator.

Stofan returned to Cleveland in 1982 as Lewis' fifth Center Director charged with the task of implementing Lewis' first strategic plan. The center had never had major roles in Manned Space Flight projects, but Stofan saw these big programs as an opportunity to make Lewis more visible within NASA. Stofan aimed for five major projects for the Center: the power system for the space station, the Advanced Turboprop Program, renovations of the Altitude Wind Tunnel (AWT) for expanded icing research, the Advanced Communications Technology Satellite Program and the Shuttle/Centaur Program. Amazingly, he secured funding for all but the AWT renovations. Most of the programs in the first strategic plan are still thriving.

Present day at his home on the slopes of Steamboat Springs, ColoIn addition to implementing the center's strategic plan, Stofan instituted a new management style. He advocated participative management over the autocratic management style of the 1970s. His outstanding work managing advanced research and technology programs for NASA earned him the 1985 Presidential Rank Award for Distinguished Executives.

Following the Challenger tragedy in January 1986, NASA asked Stofan to return to Headquarters as the Associate Administrator for the Space Station Office where he led the negotiations of the international technical agreements and the U.S. contract to build the space station until his retirement on April 1, 1988. He continued to work in the aerospace industry for the next 10 years.

Stofan and his wife, Barbara have settled into a new lifestyle and home 7200 feet up into the mountains of Steamboat Springs, Colo., where he can daily enjoy one of his favorite past times—downhill skiing. He also enjoys golfing and building furniture. The couple travel extensively, including a recent trip to Maui to celebrate their 75th birthdays; to Ohio three times a year to Hiram College for Board Meetings where he has served as a trustee for the past 25 years; and to Virginia and New York to visit their daughters and five grandchildren. His daughter, Dr. Ellen Stofan, is a planetary geologist known for her work on Venus and Titan. His other daughter, Lynn, is an attorney.

Friday, April 9, 2010

The Spirit of Pete Conrad Lives on at Innovation Summit

The student team from Monta Vista High School in CupertinoA lunar habitat module, paper that captures sound as energy and a drug delivery system for use in space. What do these inventions have in common? They’re all concepts being developed for commercialization by high school students competing in the Conrad Foundation’s Innovation Summit.

The summit is being held April 8-10, 2010 at NASA’s Ames Research Center, Moffett Field, Calif. The "Spirit of Innovation" award is in honor of the late Charles 'Pete' Conrad, a highly decorated naval aviator and astronaut who flew Gemini V, Gemini XI, commanded Apollo XII and was the third person to walk on the moon. Conrad went on to fly Skylab, our first space station. He received a Congressional Space Medal of Honor for his work on Skylab.

Nancy Conrad, wife of the late Pete Conrad, serves as chairman of the Conrad Foundation. She formed the program to provide high school students with an understanding of science and technology and give them an opportunity to solve real world problems through innovation and entrepreneurship.

During the three-day event, 25 teams from all over the U.S. present their ideas to a panel of experts similar to the way start-up entrepreneurs "pitch" to potential investors. The teams create an online portfolio (videos, blog and "company" logo) to present to venture capitalists, entrepreneurs and scientists.

Winning teams receive an opportunity to commercialize the technology and $5,000 in seed money to further develop the product.

"Our goal is to excite students about science, technology and innovation by connecting them with top entrepreneurs, scientists and industry leaders," said Joshua Neubert, executive director for the Conrad Foundation.

Niveditha Jayasekar, a student from Monta Vista High School in Cupertino, Calif., said she became fascinated with nanotechnology as early as the sixth grade. Jayasekar and her four teammates are using a patented nanotechnology developed by NASA scientist Dr. David Loftus to deliver pharmaceuticals in microgravity. The team hopes the product could lead to future breakthroughs in the field of space medicine.

Monta Vista High School teacher Carl Schmidt is the team’s advisor and representative for Future Business Leaders of America. Schmidt said contrary to most science competitions, students in the Conrad Innovation Summit approach projects with an entrepreneurial mindset. "They need to think about who has a problem and will pay to get it solved," Schmidt said. "The goal is to take a technological idea to the commercial market."

Schmidt said the students gain experience working with scientists as well as an understanding of the market. He adds that the competition, which has 30 percent female participation, is a unique way to recruit more females into science and technology fields.

The 25 finalist teams will compete in four categories: aerospace exploration, renewable energy, green schools and space nutrition. Beginning March 29, 2010, the public can visit the Conrad Foundation Web site and vote for their favorite team. Winners for the People’s Choice Awards will be announced on April 10, 2010.

For more information about the Conrad Innovation Summit, visit:


Thursday, April 8, 2010

NASA Study Finds Atlantic 'Conveyor Belt' Not Slowing

overturning circulation of the global ocean
Illustration depicting the overturning circulation of the global ocean. Throughout the Atlantic Ocean, the circulation carries warm waters (red arrows) northward near the surface and cold deep waters (blue arrows) southward. › Larger image
New NASA measurements of the Atlantic Meridional Overturning Circulation, part of the global ocean conveyor belt that helps regulate climate around the North Atlantic, show no significant slowing over the past 15 years. The data suggest the circulation may have even sped up slightly in the recent past.

The findings are the result of a new monitoring technique, developed by oceanographer Josh Willis of NASA's Jet Propulsion Laboratory in Pasadena, Calif., using measurements from ocean-observing satellites and profiling floats. The findings are reported in the March 25 issue of Geophysical Research Letters.

The Atlantic overturning circulation is a system of currents, including the Gulf Stream, that bring warm surface waters from the tropics northward into the North Atlantic. There, in the seas surrounding Greenland, the water cools, sinks to great depths and changes direction. What was once warm surface water heading north turns into cold deep water going south. This overturning is one part of the vast conveyor belt of ocean currents that move heat around the globe.

Without the heat carried by this circulation system, the climate around the North Atlantic -- in Europe, North America and North Africa -- would likely be much colder. Scientists hypothesize that rapid cooling 12,000 years ago at the end of the last ice age was triggered when freshwater from melting glaciers altered the ocean's salinity and slowed the overturning rate. That reduced the amount of heat carried northward as a result.

Until recently, the only direct measurements of the circulation's strength have been from ship-based surveys and a set of moorings anchored to the ocean floor in the mid-latitudes. Willis' new technique is based on data from NASA satellite altimeters, which measure changes in the height of the sea surface, as well as data from Argo profiling floats. The international Argo array, supported in part by the National Oceanic and Atmospheric Administration, includes approximately 3,000 robotic floats that measure temperature, salinity and velocity across the world's ocean.

With this new technique, Willis was able to calculate changes in the northward-flowing part of the circulation at about 41 degrees latitude, roughly between New York and northern Portugal. Combining satellite and float measurements, he found no change in the strength of the circulation overturning from 2002 to 2009. Looking further back with satellite altimeter data alone before the float data were available, Willis found evidence that the circulation had sped up about 20 percent from 1993 to 2009. This is the longest direct record of variability in the Atlantic overturning to date and the only one at high latitudes.

The latest climate models predict the overturning circulation will slow down as greenhouse gases warm the planet and melting ice adds freshwater to the ocean. "Warm, freshwater is lighter and sinks less readily than cold, salty water," Willis explained.

For now, however, there are no signs of a slowdown in the circulation. "The changes we're seeing in overturning strength are probably part of a natural cycle," said Willis. "The slight increase in overturning since 1993 coincides with a decades-long natural pattern of Atlantic heating and cooling."

If or when the overturning circulation slows, the results are unlikely to be dramatic. "No one is predicting another ice age as a result of changes in the Atlantic overturning," said Willis. "Even if the overturning was the Godzilla of climate 12,000 years ago, the climate was much colder then. Models of today's warmer conditions suggest that a slowdown would have a much smaller impact now.

"But the Atlantic overturning circulation is still an important player in today's climate," Willis added. "Some have suggested cyclic changes in the overturning may be warming and cooling the whole North Atlantic over the course of several decades and affecting rainfall patterns across the United States and Africa, and even the number of hurricanes in the Atlantic."

With their ability to observe the Atlantic overturning at high latitudes, Willis said, satellite altimeters and the Argo array are an important complement to the mooring and ship-based measurements currently being used to monitor the overturning at lower latitudes. "Nobody imagined that this large-scale circulation could be captured by these global observing systems," said Willis. "Their amazing precision allows us to detect subtle changes in the ocean that could have big impacts on climate."

For more information about NASA and agency programs, visit: http://www.nasa.gov.

JPL is managed for NASA by the California Institute of Technology in Pasadena.

Wednesday, April 7, 2010

NASA's Grace Sees Rapid Spread in Greenland Ice Loss

Changes in Greenland's ice mass as measured by NASA's Gravity  Recovery and Climate Experiment (Grace) mission between September 2005  (left) and September 2008 (right)A new international study finds that ice losses from Greenland's ice sheet, which have been increasing over the past decade in its southern region, are now spreading rapidly up its northwest coast.
The researchers, including Isabella Velicogna, jointly of NASA's Jet Propulsion Laboratory, Pasadena, Calif., and the University of California, Irvine, compared data from the JPL-built and managed Gravity Recovery and Climate Experiment (Grace) mission with continuous GPS measurements made from long-term sites on bedrock on the ice sheet's edges. The Grace and GPS data gave the researchers monthly averages of crustal uplift caused by ice mass loss. They found that the acceleration in ice loss began moving up the northwest coast of Greenland in late 2005. The authors speculate the dramatic ice mass losses on Greenland's northwest coast are caused by some of the big glaciers in the region sliding downhill faster and dumping more ice into the sea.

"These changes on the Greenland ice sheet are happening fast, and we are definitely losing more mass than we had anticipated," says Velicogna. "We also are seeing this trend in Antarctica, a sign that warming temperatures really are having an effect on ice in Earth's cold regions."

The NASA/National Science Foundation-funded study was led by Shfaqat Abbas Khan of the Denmark Technical Institute's National Space Institute in Copenhagen. Other participating institutions included the University of Colorado at Boulder and Ohio State University, Columbus.

Link for more information:

Tuesday, April 6, 2010

A Burst of Spring

A Burst of Spring
Spring has sprung on Mars, bringing with it the disappearance of carbon dioxide ice (dry ice) that covers the north polar sand dunes. In spring, the sublimation of the ice (going directly from ice to gas) causes a host of uniquely Martian phenomena.

In this image streaks of dark basaltic sand have been carried from below the ice layer to form fan-shaped deposits on top of the seasonal ice. The similarity in the directions of the fans suggests that they formed at the same time, when the wind direction and speed was the same. They often form along the boundary between the dune and the surface below.

Monday, April 5, 2010

NASA Astrobiology Institute ‘Removes Walls’ for Virtual Conference

Dale Cruikshank and David Des Marais at NASA Ames Research Center  talk to George Cody at the Carnegie Institution of Washington and other  videoconferencing rooms at research sites across the countryA virtual "Workshop Without Walls" conference hosted last week by the NASA Astrobiology Institute (NAI) drew more than 170 registrants from 21 states and 16 foreign countries.

Entitled "The Organic Continuum from the Interstellar Medium to the Early Earth," the two-day workshop held March 11-12, 2010 was organized by George Cody, leader of the NAI's Carnegie Institution of Washington team and Doug Whittet, leader of the NAI’s team at the Rensselaer Polytechnic Institute, Troy, New York.

Among the countries represented at the workshop were Canada, Mexico, six western European nations, Ukraine, India, South Korea, Japan, Australia, Brazil, Colombia, and Uruguay.

"The Workshop was in many ways a realization of the original vision of the virtual institute,"said Carl Pilcher, director of the NAI. "When the NAI began 12 years ago, we envisioned scientists interacting seamlessly at a distance. But the technology and the culture weren't ready. Today the technology works beautifully, and people have come to see this as the wave of the future. This workshop demonstrated that the future has arrived."

A total of 33 scientific talks were presented during the workshop, with interactive question and answer capability provided for the participants at eight sites equipped with high definition video and audio, and streaming with real-time question submission through the Adobe Connect web interface.

"The advances in technology that made this meeting possible have been paralleled by remarkable developments in the research that drives the science," Whittet said. "The benefit in terms of scientific knowledge gained and dollars expended by participants is likely unprecedented," added Cody.

According to Cody, the conference was "an experiment." Most participants categorized their experience level with remote collaborative technologies as beginner or intermediate, and a few had no prior experience at all.

Despite this, participants reported the experiment was a great success. "I was not expecting to have the same intellectual experience as I normally do at conferences…but after this conference, I do have that same sense of having been to a "real" conference,” adding, "this was very fulfilling for me professionally," said one participant.

Locations of participants ranged from a conference room in a major city with high-speed connectivity and professional videoconferencing equipment, to a home office in a small town with a laptop and home-based Internet connection.

"Over the course of the conference, I actually came to be unaware of the conference as being at multiple venues,"Cody said, "…the difference that high definition, high band-width videoconferencing makes is remarkable. Clear face-to-face contact with no time lag in either visual or audio was the essential part. Evidently the difference between 100 feet and 3000 miles is not all that great."

NAI is preparing guidelines for those in the community who are interested in hosting such an event in the future. Information will be available shortly, but interested parties can contact Marco Boldt at NAI Central at any time, marco.boldt@nasa.gov

Friday, April 2, 2010

NASA Mars Rover Getting Smarter as it Gets Older

Images taken through three of the filters in Opportunity's new  software are combined into this approximately true-color view of the  rock, which is about the size of a footballNASA's Mars Exploration Rover Opportunity, now in its seventh year on Mars, has a new capability to make its own choices about whether to make additional observations of rocks that it spots on arrival at a new location.
Software uploaded this winter is the latest example of NASA taking advantage of the twin Mars rovers' unanticipated longevity for real Martian test drives of advances made in robotic autonomy for future missions.
Now, Opportunity's computer can examine images that the rover takes with its wide-angle navigation camera after a drive, and recognize rocks that meet specified criteria, such as rounded shape or light color. It can then center its narrower-angle panoramic camera on the chosen target and take multiple images through color filters.
"It's a way to get some bonus science," said Tara Estlin of NASA's Jet Propulsion Laboratory, Pasadena, Calif. She is a rover driver, a senior member of JPL's Artificial Intelligence Group and leader of development for this new software system.
The new system is called Autonomous Exploration for Gathering Increased Science, or AEGIS. Without it, follow-up observations depend on first transmitting the post-drive navigation camera images to Earth for ground operators to check for targets of interest to examine on a later day. Because of time and data-volume constraints, the rover team may opt to drive the rover again before potential targets are identified or before examining targets that aren't highest priority.
This false color view results from the first observation of a  target selected autonomously by a spacecraft on Mars
The first images taken by a Mars rover choosing its own target show a rock about the size of a football, tan in color and layered in texture. It appears to be one of the rocks tossed outward onto the surface when an impact dug a nearby crater. Opportunity pointed its panoramic camera at this unnamed rock after analyzing a wider-angle photo taken by the rover's navigation camera at the end of a drive on March 4. Opportunity decided that this particular rock, out of more than 50 in the navigation camera photo, best met the criteria that researchers had set for a target of interest: large and dark.
"It found exactly the target we would want it to find," Estlin said. "This checkout went just as we had planned, thanks to many people's work, but it's still amazing to see Opportunity performing a new autonomous activity after more than six years on Mars."
Opportunity can use the new software at stopping points along a single day's drive or at the end of the day's drive. This enables it to identify and examine targets of interest that might otherwise be missed.
"We spent years developing this capability on research rovers in the Mars Yard here at JPL," said Estlin. "Six years ago, we never expected that we would get a chance to use it on Opportunity."
NASA's Mars Exploration Rover Opportunity took this image in  preparation for the first autonomous selection of an observation target  by a spacecraft on Mars
The developers anticipate that the software will be useful for narrower field-of-view instruments on future rovers.
Other upgrades to software on Opportunity and its twin, Spirit, since the rovers' first year on Mars have improved other capabilities. These include choosing a route around obstacles and calculating how far to reach out a rover's arm to touch a rock. In 2007, both rovers gained the know-how to examine sets of sky images to determine which ones show clouds or dust devils, and then to transmit only the selected images. The newest software upload takes that a step further, enabling Opportunity to make decisions about acquiring new observations.
The AEGIS software lets scientists change the criteria it used for choosing potential targets. In some environments, rocks that are dark and angular could be higher-priority targets than rocks that are light and rounded, for example.
This new software system has been developed with assistance from NASA's Mars Exploration Rover Project and with funding from the New Millennium Program, the Mars Technology Program, the JPL Interplanetary Network Development Program, and the Intelligent Systems Program. The New Millennium Program tests advanced technology in space flight. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover Project for the NASA Science Mission Directorate, Washington.
More information about the Mars rovers is online at: http://www.nasa.gov/rovers. More information about AEGIS is at: http://scienceandtechnology.jpl.nasa.gov/newsandevents/newsdetails/?NewsID=677.